I should have a follow-up or two for you when I'm not constrained by the length of a lunch break. (In the event that doesn't happen [busy week], feel free to expound regarding Michio Hikitsuchi, who reportedly codified the "Rites of Spring", which includes IP exercises that are somewhat well known in the aikido world, e.g. torifune and furitama (though moreso as "use these as warm up because the founder did 'em so we do 'em" exercises); and whose Shingu Bojutsu solo kata, for which Morihei Ueshiba reportedly provided Hikitsuchi formal documentation, bears resemblance to Ueshiba's documented personal jo solo work, based on video available online
I think it would be profitable to make a timeline of Morihei Ueshiba’s personal training regime (assuming he had one), the other martial artists he met, and also the students whom he taught and when he started teaching them. This would also provide a useful context for discussions concerning the ‘purity’ of aikido.
I think we can make a few rough divisions to begin with:
1. The period from his youth and early dabbling in bujutsu until the time he went to Hokkaido, including his early training in fishing, possibly farming, sumo and other bujutsu, and also including his time in the military and his participation in the Russo-Japanese War of 1904-1905 [1883 – 1912].
2. The period in Hokkaido until he returned to Tanabe to see his sick father [1912 – 1920]. Takeda Sokaku is the crucial figure here, beginning a relationship that lasted at least until 1936.
3. The period from the first meeting with Onisaburo Deguchi and his move to Ayabe to join the Omoto religion and to train Omoto followers, including his early encounters with Isamu Takeshita and the military officers from the naval base at Maizuru, until his move to Tokyo. This would also include the early chinkon
training and the trip to Mongolia [1920 – 1926].
4. The period from his final settling in Tokyo until he retired to Iwama [1926 – 1931]. Kenji Tomiki became a student at this time, as did Kanemoto Sunadomari.
5. The period of the Kobukan Dojo and the uchi-deshi [1931 – 1942]. This period saw his involvement with ultranationalists, his supposed ‘break’ with Takeda Sokaku and also Onisaburo Deguchi (c. 1935 – 36), and his career as a military teacher at Japan’s army and naval academies. Apart from Tomiki, his students included Shirata, Iwata, Mochizuki, Murashige, Sugino, and, later, Shioda, Kisaburo Osawa, and Koichi Tohei.
6. The period of seclusion in Iwama [1942 – 1950 / 1955]. Senior postwar students like Arikawa, Yamaguchi and Tada joined the Tokyo Dojo, while Saito and, later, Isoyama trained in Iwama. Michio Hikitsuchi and Hirokazu Kobayashi also began regular training in this period.
7. The period from his emergence from Iwama until his death, including his trips around Japan and to Hawaii [1950 / 1955 – 1969]. In this period, we know that he travelled round Japan quite regularly, stopping off especially at Osaka (Abe Seiseki, Kobayashi Hirokazu), Shingu (Hikitsuchi Michio), and Kumamoto (the Sunadomari brothers), and with occasional visits to Wakayama and Tanabe. In this period the postwar deshi joined the Tokyo dojo, such as Tamura, Yamada, Saotome and Chiba.
The point of this chronology is to suggest (1) that the spiritualization of his training would probably begin in Period 3, with Omoto and his chinkon / kishin and misogi training, (2) that it might be possible to map some sort of IP training right from Period 2, if not before, and that (3) the ‘Rites of Spring’ taught to Hikitsuchi in Periods 6 and 7 would be the distillation of intensive personal training of some sort (including what we would call IP), right from the beginning. This training might also include plenty of trial and error, and also include Ueshiba progressively becoming aware of the strengths, weaknesses and pitfalls of this training. Did he ever have a teaching plan?